Investments - Schedule of Maturities for Fixed Income Securities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Amortized cost, net
Due in one year or less	$ 1,464	$ 1,544
Due after one year through five years	22,582	22,889
Due after five years through ten years	21,538	17,431
Due after ten years	9,712	10,526
Subtotal	55,296	52,390
ABS and MBS	3,434	1,226
Amortized cost, net	58,730	53,616
Fair value
Due in one year or less	1,460	1,531
Due after one year through five years	22,706	22,595
Due after five years through ten years	21,780	17,130
Due after ten years	9,691	10,250
Subtotal	55,637	51,506
ABS and MBS	3,478	1,241
Fair value	$ 59,115	$ 52,747